Abstract

A survey on drinking water quality was conducted in 1990/1991 to evaluate the impact of organic matters particularly of nitrate-nitrite contamination in raw water. Water samples were taken from Water Supply Enterprices (WSE) in Jakarta, i.e Pejompongan WSE and Pulogadung WSE. The results showed that the treatment efficiency of Pejompongan WSE to reduce nitrate and nitrite concentration was 5% and 82.1% respectively, and that of Pulogadung WSE were 50.0% and 63.2%. The concentration of nitrate in water the supply from Pejompongan WSE and Pulogadung WSE in general is in accordance with the water quality standard. The nitrite level in the water supply from Pejompongan also met the standard, while from Pulogadung did not. It has been observed that the nitrite concentration in water from Pejompongan distribution pipe is increasing with the distance from water treatment installation.